Among touch screen technologies, comparing with a resistive touch screen, a capacitive touch screen has advantages such as long service life, high light transmittance and multi-touch support. Furthermore, in the capacitive touch screen, noises and parasitic capacitance relative to the ground are well suppressed. Therefore, the capacitive touch screen has become one of hot spots in touch screen manufacturing industry nowadays. The capacitive touch screens can be classified into two categories, i.e. a self-capacitive touch screen and a mutual-capacitive touch screen. In the self-capacitive touch screen, merely one layer of touch electrodes is arranged, and a touch operation may be easily detected by determining whether self capacitances of the respective touch electrodes are changed. Therefore, the self-capacitive touch screen has advantages such as simple structure and easy implementation.
In recent years, a trend in the industry is to manufacture the display device with a thinner thickness. As a result, display panel manufactures are in favor of embedding the touch electrodes of the touch screen into a display panel of a built-in touch display device, so as to reduce the thickness of the display device, meanwhile it enables to significantly reduce cost for manufacturing the touch display devices.